/*
 * Copyright 2023 devaper
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package io.github.devaper.pigeon.support

import io.github.devaper.pigeon.exception.*
import io.github.devaper.pigeon.handler.method.*
import java.lang.reflect.*

/**
 * Client的调用处理器, 最简单实现, 仅仅负责转发调用到 [MethodHandler]
 *
 * 调用链：
 * 用户调用 -> JDK代理对象 -> [SimpleClientInvocationHandler] -> [MethodHandler] , 然后再一层层返回结果
 */
class SimpleClientInvocationHandler(
    val methodHandlerMapping: MethodHandlerMapping
) : InvocationHandler {


    override fun invoke(proxy: Any, method: Method, args: Array<out Any>?): Any {
        return when(method.name) {
            "equals" -> equals(args?.firstOrNull())
            "hashCode" -> hashCode()
            "toString" -> toString()
            else -> {
                val methodHandler = methodHandlerMapping[method] ?: throw NoSuchMethodHandlerException(method)
                return methodHandler.handle(args ?: emptyArray()) as Any
            }
        }
    }
}